1. Field
Embodiments disclosed herein generally relate to a magnetic disk device employing a microwave assisted magnetic recording (MAMR) head.
2. Description of the Related Art
Over the past few years, MAMR has been studied as a recording method to improve the areal density of a magnetic read/write device, such as a hard disk drive (HDD). MAMR enabled magnetic recording heads utilize a spin torque oscillator (STO) for generating a microwave (high frequency AC magnetic field). When the magnetic field from the write head is applied and current is conducted to the STO, the STO oscillates and may provide an AC magnetic field to the media. The AC magnetic field may reduce the coercive force of the recording media, thus high quality recording by MAMR may be achieved. Typically the STO includes a spin polarization layer (SPL) for transmitting the spin polarized torque, a field generation layer (FGL) for generating the AC magnetic field, and an interlayer disposed between the SPL and the FGL.
In order to achieve higher areal density and a longer operation lifetime, an improved STO structure is needed.